Algorithms and Me: Paths in a Binary Search Tree

Traverse all paths of a given binary search tree.
Only thing is we need to do is some book keeping so that we can print the path when we reach a leaf node.

void printPath2(Node * node, int path[], int pathLen){

        int i;

        if(!node)

            return;

        path[pathLen]  = node->value;

        int isLeaf = node->left == NULL && node->right == NULL;

        if(isLeaf ){

                 for(i=0; i<=pathLen; i++)

                         printf("%d, ", path[i]);

 

                 printf("\n");

         }

        printPath2(node->left, path, pathLen+1);

        printPath2(node->right, path, pathLen+1);

        return ;

}

print only those paths which sums up to a given number

void printPath(Node * node, int sum, int path[], int pathLen){

        if(node == NULL){

                return;

        }

        int subSum =  sum - node->value;

        path[pathLen] = node->value;

        int isLeaf = node->left == NULL && node->right == NULL;

        if(isLeaf && subSum ==0){

           for(i=0; i<=pathLen; i++)

               printf("%d, ", path[i]);

           printf("\n");

        }  

        printPath(node->left, subSum, path, pathLen+1);

        printPath(node->right, subSum, path, pathLen+1);

        return ;

}

Find whether a tree contains a path with given sum

int hasPath(Node * node, int sum){

        int lpath, rpath;

        if(node == NULL)

                return sum == 0;

        int subSum =  sum - node->value;

        if(node->left == NULL && node->right == NULL)

                return subSum == 0;

        if(node->left)

                lpath = hasPath(node->left, subSum);

        if(node->right)

                rpath = hasPath(node->right, subSum);

        return rpath || lpath;

}

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